Through　researching　and　analyzing　the　causes　leading　to　the　crashes　of　the　vulnerable　road　user,　the　cross-street　behavior　violating　the　traffic　regulations　and　the　movable　obstacle　in　the　line　of　sight　are　proved　to　be　the　main　ones.　After　investigation,　some　data　describing　the　cross-street　behavior　are　collected　and　analyzed.　On　the　basis　of　it,　predict　model　of　obey　traffic　rule　is　established.　Through　applying　the　model,　some　new　and　quantized　conclusions　are　found　out.　Finally,　the　concept　of　the　endurance　of　the　vulnerable　road　user　is　defined　that　instead　of　time　unit,　the　probability　of　cross　the　street　obeying　traffic　rule　is　used.